1. Field of the Invention
The present invention relates to a precast and transportable mobile home foundation system. More specifically, the present invention relates to a method and apparatus for securing a mobile home to the ground by utilizing a plurality of elongated concrete slabs that are placed within elongated ditches formed in the ground and to which the mobile home is secured.
2. Discussion of the Related Art
Mobile homes have been used to provide a living facility that can be moved from one location to another. The typical mobile home includes a housing unit that is mounted onto a frame. The frame is usually a assembly of steel I-beams that includes wheels and a coupling section for attaching to a towing vehicle for moving the mobile home from one location to another. At the installation site the mobile home is jacked-up to remove weight from the wheels and stacks of cinder or cement blocks are placed between the ground and the I-beam frame at predetermined locations. The wheels can then be removed and the mobile home lowered into position so that it rests on the stacks of blocks that serve as its foundation.
In most states safety rules require that mobile homes be anchored to the ground to reduce the chances of them blowing over in high winds. One type of specification requires that metal strapping be used by extending it over the structure of the mobile home. This overhead strapping is typically installed during manufacture. The siding and roof are placed over the overhead strapping, with the strapping sandwiched between the mobile home upper frame structure and the siding and roof. A plurality of such straps will usually be placed along the length of the mobile home. The straps are typically flexible sheet metal, preferably galvanized steel, and are approximately 1 to 2 inches, preferably about 1.25 inches in width. The ends of the overhead straps protrude below the lower edge of the mobile home and are secured to anchors embedded in the ground.
One problem associated with the use of straps occurs during settling of the foundation. For example, as the mobile home settles, at least some of the straps can become loose. It is common that settling will not be uniform from one end and/or side of the mobile home to the other. That is, one end or side of the mobile home will usually settle more than the other end or side. Thus, from time to time the mobile home owner is faced with the expense of having to have the mobile home releveled and the straps retighened. In many cases, the homeowner ignores the loosened straps and faces the danger of the mobile home becoming unstable during high winds.
Several factors should be balanced when providing a foundation for mobile homes. One factor is the condition of the ground on which the mobile home is to be located. In some locations the surface of the ground can be relatively unstable during certain times of the year due to excessive rains or thaw. It is difficult to provide an adequate and safe foundation for a mobile home under such conditions. The mobile home often cannot be placed on such locations until the ground is considered firm enough to support the mobile home and its foundation. A second factor is that the foundation should provide enough stability to adequately prevent the mobile home from being dislodged by high winds. A third factor is that the foundation should be portable enough so that it can be moved from location to location. Also, in some locations it is important that the foundation not be considered a permanent structure in order for it to be exempt from real estate taxes and more stringent building permits. In this regard, prior art devices and techniques have been deficient insofar as those foundations that provide reasonably good support tend to be of a permanent nature, and therefor subject to taxes and more stringent permits. Additionally, those prior art support structures that are light and portable enough to be exempt from such requirements, such as stacks of cinder blocks, fail to provide the necessary stability and support for the mobile home, especially during high wind situations.
U.S. Pat. No. 3,879,905 to Catalano, Sr. discloses a previous attempt to support a mobile home on the ground that includes the use of a plurality of concrete support assemblies 20. Each of the concrete support assemblies 20 include a plurality of upwardly projecting, spaced-apart support structures 24, 26. Each of the upwardly projecting support structures 20 receives one of the steel I-beams of a mobile home. The I-beam is connected to the upwardly projecting support structure by a strap 40.
One problem associated with Catalano""s concrete support assemblies is that each assembly requires the use of two spaced apart upwardly projecting support structures 24 and 26. The upwardly projecting support structures 24, 26 are integrally formed with the base 22 during the casting of the support assembly 20. Thus, difficulties are encountered when the mobile home is wheeled on top of the concrete assemblies 20 at the dwelling location due to the interference between the I-beams 14, 16 and the upwardly projecting support structures 24, 26.
Accordingly, it is an object of the present invention to provide a precast transportable foundation system for mobile homes that can be easily positioned, even on soft ground. It is also an object of the present invention to provide a method for positioning a mobile home over a foundation structure comprised of a plurality of low profile concrete slabs and fixedly connecting it to them. It is a further object of the present invention, to provide an apparatus and method for supporting a mobile home that can be economically manufactured offsite so as to minimize the amount of time and effort required to install the supporting system at the site.
In accordance with one exemplary embodiment of the present invention there is provided a foundation system for a mobile home having a living unit supported on a steel beam frame, which foundation system comprises:
a plurality of elongated concrete slabs, each of said concrete slabs having a bottom surface, a pair of side surfaces, a pair of end surfaces, a top surface and a pair of beveled edge surfaces, each of said beveled edge surfaces extending between said top surface and one of said side surfaces;
at least two fastener assemblies each having a first portion and a second portion, said first portion being disposed within each of said concrete slabs, said second portion projecting from said top surface of said concrete slab;
at least one constraint device having a first end, a second end and a middle portion extending between said first and second ends, said first and second ends being capable of fastening to said fastener assemblies.
In a preferred embodiment of the present invention the constraint device is a flexible strap, more preferably of galvanized steel.
In another preferred embodiment of the present invention the elongated concrete slabs contain one or more blind bores at at least one of their ends.
In a preferred embodiment of the present invention there is provided a method for securing a mobile home to the ground, said mobile home having a housing containing the living facilities mounted on a steel beam frame, and wheels for supporting the frame, which method comprises:
providing at least one elongated concrete slab characterized as having a bottom surface, a pair of side surfaces, a pair of end surfaces, a top surface and a pair of beveled edge surfaces, such that each of the beveled edge surfaces extend between the top surface and one of the side surfaces;
digging at least one elongated ditch in the ground to which the mobile home is to be secured said at least one elongated ditch being at a depth that will cover at least a portion of said side surfaces;
placing said at least one elongated concrete slab in at least one of said elongated ditch at a depth such that at least the top surface is exposed;
positioning a mobile home over said concrete slab so that said elongated concrete slab is situated underneath a portion of said steel beam frame;
placing a support system between said mobile home and said concrete slab so that said steel beam frame of said mobile home rests on said support system;
securing at least two fastener assemblies to the top surface of said concrete slab so that they are aligned under a section of said steel beam so that one fastener assembly is on one side of said steel beam the other fastener assembly on the other side of said steel beam;
connecting a first end of a constraint device to one of said at least two fasteners;
passing the constraint device around the steel beam between the mobile home and said steel beam;
connecting the second end of said constraint device to the second of the at least two fasteners, thereby securing the mobile home to the concrete slab.
In a preferred embodiment of the present invention a plurality of ditches is dug, which ditches are approximately the width of said mobile home and which ditches are substantially parallel to each other and spaced a predetermined distance apart along the length of the mobile home.
In another preferred embodiment of the present invention the elongated ditches and concrete slabs are situated substantially transverse to the longitudinal axis of the mobile home.
In another preferred embodiment of the present invention the constraint device is a galvanized steel strap.